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First use of an encryption technique

First use of an encryption technique
Who
Caesar cipher
Where
France (,Gaul encompassed present-day France, Luxembourg and Belgium, most of Switzerland, the western part of northern Italy and parts of the Netherlands and Germany. ,)
When
0050 BC
The Caesar cipher was first used during the Gaul War c. 50 BC. According to the biographer Suetonius, Julius Caesar employed this cipher during his military campaigns, the first recorded use of any encryption technique. The cipher is fairly simple, and in this instance involved shifting each letter of the alphabet three places to the left to produce apparently meaningless groups of letters. The recipient of the cipher had merely to move each letter three places to the right to reveal the message from Caesar.